<!DOCTYPE html>
<html lang="en">
 <head>
  <meta charset="UTF-8">
 <title>instanceof类型判断</title>
 </head>
<body>
  <script>
    var a = new Array();
    if(a instanceof Array){
        document.write("a是一个数组类型");
    } else {
        document.write("a不是一个数组类型");
    }
  </script>
 </body>
</html>
